Update: Hmmm... I guess was thinking about Getopt::Standard. enlil's answer appears correct and my reference below is superfluous.

Try this:

#!/usr/bin/perl -w
use strict;
use Getopt::Long;
use Data::Dumper;

my %options;
GetOptions(
    \%options,
    'length|height=i' => \$options{length}
);

print Dumper \%options;
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Cheers,
Ovid

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